Codebase list widelands / HEAD CMakeLists.txt
HEAD

Tree @HEAD (Download .tar.gz)

CMakeLists.txt @HEADraw · history · blame

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
project (widelands)

cmake_minimum_required (VERSION 3.5)
cmake_policy(VERSION 3.5)

message(STATUS "Using CMake version ${CMAKE_VERSION}")

option(OPTION_USE_GLBINDING "Use glbinding instead of GLEW" OFF)
option(OPTION_GLEW_STATIC "Use static GLEW Library" OFF)
option(OPTION_BUILD_WEBSITE_TOOLS "Build website-related tools" ON)
option(OPTION_BUILD_TRANSLATIONS "Build translations" ON)
option(OPTION_BUILD_TESTS "Build tests" ON)
option(OPTION_BUILD_CODECHECK "Build codecheck" ON)
option(OPTION_BUILD_WINSTATIC "Build a static linked .exe on windows" OFF)
option(OPTION_TSAN "Build with ThreadSanitizer" OFF)
option(OPTION_FORCE_EMBEDDED_MINIZIP "Use embedded minizip sources" OFF)
option(USE_XDG "Follow XDG-Basedir specification" ON) # Enabled by default

# Absolute path reference for submodules
set(WL_ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}")

# Add custom includes to override system libs
FILE(GLOB custom_include_directories auto_dependencies/*)
foreach(custom_include_dir ${custom_include_directories})
  if(IS_DIRECTORY "${custom_include_dir}")
    message(STATUS "Using custom include directory '${custom_include_dir}'.")
    list(INSERT CMAKE_INCLUDE_PATH 0 "${custom_include_dir}")
    include_directories(BEFORE SYSTEM "${custom_include_dir}")
  else()
    message(WARNING "Not a directory: '${custom_include_dir}' - Ignored.")
  endif()
endforeach()

include("${CMAKE_SOURCE_DIR}/cmake/UseSystemInfo.cmake")
include("${CMAKE_SOURCE_DIR}/cmake/WlFunctions.cmake")

# This policy is not known to versions prior 3.11 and would result in errors,
# if set on such systems. This can be removed when cmake_minimum_required is set
# to 3.11 or newer  by using:
# cmake_policy(VERSION 3.11)
if(POLICY CMP0072)
  cmake_policy(SET CMP0072 NEW)

  # TODO(stonerl): Check on later Ubuntu releases whether this workaround is
  # still needed or not.
  # --- Seems to work fine on 21.04
  if (CMAKE_SYSTEM MATCHES "Linux")
    distro_name (DISTRO_NAME)
    # DISTRO_NAME is different on the build-servers.
    if ((DISTRO_NAME MATCHES "Ubuntu 18.10" OR DISTRO_NAME MATCHES "Cosmic"
         OR DISTRO_NAME MATCHES "Ubuntu 19.04" OR DISTRO_NAME MATCHES "Disco"
         OR DISTRO_NAME MATCHES "Ubuntu 19.10" OR DISTRO_NAME MATCHES "Eoan"
         OR DISTRO_NAME MATCHES "Ubuntu 20.04" OR DISTRO_NAME MATCHES "Focal")
        AND CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
      cmake_policy(SET CMP0072 OLD)
    endif()
  endif()
endif(POLICY CMP0072)

# This policy is not known to versions prior 3.12 and would result in errors,
# if set on such systems. This can be removed when cmake_minimum_required is set
# to 3.12 or newer  by using:
# cmake_policy(VERSION 3.12)
if(POLICY CMP0074)
  cmake_policy(SET CMP0074 NEW)
endif(POLICY CMP0074)

IF(USE_XDG AND NOT APPLE AND NOT WIN32)
  ADD_DEFINITIONS(-DUSE_XDG)
  message(STATUS "Building with XDG support")
ENDIF(USE_XDG AND NOT APPLE AND NOT WIN32)

if (CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR)
  message(FATAL_ERROR "Build directory and source directory must not be the same.")
endif (CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR)

# Define the directory structure for installation - will be hardcoded in WL bin
# (through config.h). If not specified, we are going to use the directory where
# the executable is in. Also on Linux.
# Packagers (or people using make install) have to set this variable to an absolute path.
wl_set_if_unset(WL_INSTALL_BASEDIR ".")

# Define the directory structure for installation of the data files - will be hardcoded
# in WL bin (through config.h). If not specified, we are going to use the "data" directory
# below the directory where the executable is in. Also on Linux.
# Packagers (or people using make install) have to set this variable to an absolute path.
wl_set_if_unset(WL_INSTALL_DATADIR "./data")

# To override this, use '-DWL_INSTALL_BINDIR=<absolute path>' when configuring or change
# 'CMAKE_INSTALL_PREFIX'.
# Example: to have the bin installed to "/usr/games", just use '-DCMAKE_INSTALL_PREFIX=/usr'
# and don't specify '-DWL_INSTALL_BINDIR' when configuring.
# Note: 'CMAKE_INSTALL_PREFIX' defaults to /usr/local on UNIX and c:/Program Files/${PROJECT_NAME} on Windows
wl_set_if_unset(WL_INSTALL_BINDIR "${CMAKE_INSTALL_PREFIX}/games")

if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.8)
    message(FATAL_ERROR "Widelands needs GCC >= 4.8 to compile.")
  endif()
elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.4)
    message(FATAL_ERROR "Clang version must be at least 3.4!")
  endif()
elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
  if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 3.4)
    message(FATAL_ERROR "MSVC version must be at least 19!")
  endif()
else()
  message(WARNING "You are using an unsupported compiler! Supported are Clang and GCC.")
endif()
message(STATUS "Picking up default CXX flags:
    - CMAKE_CXX_FLAGS='${CMAKE_CXX_FLAGS}'
    - CMAKE_CXX_FLAGS_RELEASE='${CMAKE_CXX_FLAGS_RELEASE}'
    - CMAKE_CXX_FLAGS_DEBUG='${CMAKE_CXX_FLAGS_DEBUG}'")

SET(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${CMAKE_CURRENT_SOURCE_DIR}/cmake/Modules)

if (WIN32)
  link_libraries(wsock32 ws2_32 bcrypt)
endif()
if (OPTION_BUILD_WINSTATIC)
  add_definitions(-DGLBINDING_STATIC_DEFINE -DNGHTTP2_STATICLIB)
  if(NOT MSVC)
    if (CMAKE_SIZEOF_VOID_P EQUAL 8)
      set(PNG_LIBRARY_RELEASE "C:/msys64/mingw64/lib/libpng.a" CACHE INTERNAL "")
      set(SDL2_IMAGE_LIBRARY "C:/msys64/mingw64/lib/libSDL2_image.a" CACHE INTERNAL "")
      set(ZLIB_LIBRARY_RELEASE "C:/msys64/mingw64/lib/libz.a" CACHE INTERNAL "")
      set(SDL2_TTF_LIBRARY "C:/msys64/mingw64/lib/libSDL2_ttf.a" CACHE INTERNAL "")
      set(SDL2_MIXER_LIBRARY "C:/msys64/mingw64/lib/libSDL2_mixer.a" CACHE INTERNAL "")
      set(SDL2_LIBRARY "C:/msys64/mingw64/lib/libSDL2.a" CACHE INTERNAL "")
      set(SDL2MAIN_LIBRARY "C:/msys64/mingw64/lib/libSDL2main.a" CACHE INTERNAL "")
      set(ICU_UC_LIBRARY_RELEASE "C:/msys64/mingw64/lib/libicuuc.a" CACHE INTERNAL "")
      set(ICU_DT_LIBRARY_RELEASE "C:/msys64/mingw64/lib/libicudt.a" CACHE INTERNAL "")
      set(Intl_LIBRARY "C:/msys64/mingw64/lib/libintl.a" CACHE INTERNAL "")
    else()
      set(PNG_LIBRARY_RELEASE "C:/msys64/mingw32/lib/libpng.a" CACHE INTERNAL "")
      set(SDL2_IMAGE_LIBRARY "C:/msys64/mingw32/lib/libSDL2_image.a" CACHE INTERNAL "")
      set(ZLIB_LIBRARY_RELEASE "C:/msys64/mingw32/lib/libz.a" CACHE INTERNAL "")
      set(SDL2_TTF_LIBRARY "C:/msys64/mingw32/lib/libSDL2_ttf.a" CACHE INTERNAL "")
      set(SDL2_MIXER_LIBRARY "C:/msys64/mingw32/lib/libSDL2_mixer.a" CACHE INTERNAL "")
      set(SDL2_LIBRARY "C:/msys64/mingw32/lib/libSDL2.a" CACHE INTERNAL "")
      set(SDL2MAIN_LIBRARY "C:/msys64/mingw32/lib/libSDL2main.a" CACHE INTERNAL "")
      set(ICU_UC_LIBRARY_RELEASE "C:/msys64/mingw32/lib/libicuuc.a" CACHE INTERNAL "")
      set(ICU_DT_LIBRARY_RELEASE "C:/msys64/mingw32/lib/libicudt.a" CACHE INTERNAL "")
      set(Intl_LIBRARY "C:/msys64/mingw32/lib/libintl.a" CACHE INTERNAL "")
    endif()
  endif()
  set (OPTION_GLEW_STATIC ON)
endif()

find_package (PythonInterp REQUIRED)

find_package(Gettext REQUIRED)
find_package(OpenGL REQUIRED)
find_package(PNG REQUIRED)

find_package(SDL2 REQUIRED)
find_package(SDL2_image REQUIRED)
find_package(SDL2_mixer REQUIRED)
find_package(SDL2_ttf REQUIRED)
find_package(ZLIB REQUIRED)
if(${CMAKE_VERSION} VERSION_LESS 3.9.0)
    find_package(ICU_old REQUIRED)
else()
    find_package(ICU REQUIRED COMPONENTS uc dt)
endif()
if(OPTION_USE_GLBINDING)
  find_package(glbinding REQUIRED)
else()
  find_package(GLEW REQUIRED)
endif()

# Check that Asio is installed. Asio does not have (or need) a Find… CMake Module, so we "only" need to check if the header exists.
if(NOT asio_location OR asio_location STREQUAL "")
  unset(asio_location CACHE)
  find_path(asio_location "asio.hpp")
  if(asio_location)
    message(STATUS "Found Asio in '${asio_location}'.")
  else()
    message(FATAL_ERROR "Could NOT find Asio (missing: asio.hpp). Please run:\n./install-dependencies.sh\nwhich will attempt to install all missing dependencies automatically, or provide further instructions if this not supported on your system.")
  endif()
endif()
add_definitions(-DASIO_STANDALONE)

if (APPLE OR WIN32 OR
    CMAKE_SYSTEM_NAME MATCHES "FreeBSD" OR
    CMAKE_SYSTEM_NAME MATCHES "OpenBSD")
  if (NOT CMAKE_SYSTEM_NAME MATCHES "kFreeBSD")
    find_package(Intl REQUIRED)
  endif()
endif()

# Disable no symbols warning on macOS, but only on versions where this is
# supported. It is not supported on OS X 10.7 (DARWIN_MAJOR_VERSION == 11).
if (APPLE)
    if (${DARWIN_MAJOR_VERSION} GREATER 11)
        SET(CMAKE_C_ARCHIVE_CREATE   "<CMAKE_AR> Scr <TARGET> <LINK_FLAGS> <OBJECTS>")
        SET(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> Scr <TARGET> <LINK_FLAGS> <OBJECTS>")
        SET(CMAKE_C_ARCHIVE_FINISH   "<CMAKE_RANLIB> -no_warning_for_no_symbols -c <TARGET>")
        SET(CMAKE_CXX_ARCHIVE_FINISH "<CMAKE_RANLIB> -no_warning_for_no_symbols -c <TARGET>")
    endif()
endif()

# TODO(sirver): One day, this should be enabled. Then we have no more cycles in our dependencies....
# set_property(GLOBAL PROPERTY GLOBAL_DEPENDS_NO_CYCLES ON)

if (NOT CMAKE_BUILD_TYPE OR CMAKE_BUILD_TYPE STREQUAL "")
  find_path(FILE_WL_RELEASE "WL_RELEASE" ${CMAKE_CURRENT_SOURCE_DIR})
  if(${FILE_WL_RELEASE} STREQUAL "FILE_WL_RELEASE-NOTFOUND")
    set(CMAKE_BUILD_TYPE Debug)
  else()
    set(CMAKE_BUILD_TYPE Release)
  endif()
endif (NOT CMAKE_BUILD_TYPE OR CMAKE_BUILD_TYPE STREQUAL "")

if(CMAKE_BUILD_TYPE STREQUAL "Debug")
  set(WL_DEBUG_FLAGS "-DDEBUG")
  if(NOT MSVC)
    wl_add_flag(WL_DEBUG_FLAGS "-g")
    if(NOT OPTION_TSAN)
      option(OPTION_ASAN "Build with AddressSanitizer" ON)
    endif()
  endif()
elseif(CMAKE_BUILD_TYPE STREQUAL "Release")
  if(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 6.2))
    message(STATUS "GCC >6.2.0 breaks -O3, setting -O2")
    set(WL_OPTIMIZE_FLAGS "-O2")
  elseif(MSVC)
    set(WL_OPTIMIZE_FLAGS "/O2")
  else()
    set(WL_OPTIMIZE_FLAGS "-O3")
  endif ()
  if(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 7.0))
    message(WARNING "GCC <7.0.0 is known to cause segfaults in release builds. Please consider upgrading to GCC version 7 or newer or using Clang. Adding selected overrides to suppress reporting of known bugs.")
    wl_add_flag(WL_OPTIMIZE_FLAGS "--param asan-stack=0")
  endif()
  set(WL_DEBUG_FLAGS "-DNDEBUG -DNOPARACHUTE")
  option(OPTION_ASAN "Build with AddressSanitizer" OFF)
elseif(CMAKE_BUILD_TYPE STREQUAL "RelWithDebInfo")
  if(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 6.2))
    message(STATUS "GCC >6.2.0 breaks -O3, setting -O2")
    set(WL_OPTIMIZE_FLAGS "-O2")
  elseif(MSVC)
    set(WL_OPTIMIZE_FLAGS "/O2")
  else()
    set(WL_OPTIMIZE_FLAGS "-O3")
  endif ()
  set(WL_DEBUG_FLAGS "-DNDEBUG -DNOPARACHUTE")
  if(NOT OPTION_TSAN)
    option(OPTION_ASAN "Build with AddressSanitizer" ON)
  endif()
elseif(CMAKE_BUILD_TYPE STREQUAL "None")
  message(STATUS "Not setting any default flags.")
else()
  message(FATAL_ERROR "Unknown CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
endif()

if(OPTION_TSAN)
  message(STATUS "Using ThreadSanitizer https://clang.llvm.org/docs/ThreadSanitizer.html")
  wl_add_flag(WL_COMPILE_DIAGNOSTICS "-fsanitize=thread")
  set (CMAKE_EXE_LINKER_FLAGS "-fsanitize=thread" CACHE STRING "Set by widelands CMakeLists.txt" FORCE)
  option(OPTION_ASAN "Build with AddressSanitizer" OFF)
else()
  message(STATUS "Not using ThreadSanitizer.")
endif(OPTION_TSAN)

if(OPTION_ASAN)
  message(STATUS "Using AddressSanitizer https://clang.llvm.org/docs/AddressSanitizer.html")
  # See https://clang.llvm.org/docs/AddressSanitizer.html
  wl_add_flag(WL_COMPILE_DIAGNOSTICS "-fsanitize=address")
  wl_add_flag(WL_COMPILE_DIAGNOSTICS "-fno-omit-frame-pointer")
  set (CMAKE_EXE_LINKER_FLAGS "-fsanitize=address" CACHE STRING "Set by widelands CMakeLists.txt" FORCE)
else()
  message(STATUS "Not using AddressSanitizer.")
endif(OPTION_ASAN)

if(OPTION_ASAN AND OPTION_TSAN)
  message(FATAL_ERROR "OPTION_ASAN and OPTION_TSAN cannot be used together")
endif()

# This is set to avoid linker errors when using GLVND-libs on Linux
if("${OpenGL_GL_PREFERENCE}" STREQUAL "GLVND")
   link_libraries(OpenGL::GL)
   add_compile_definitions(WL_USE_GLVND)
   message(STATUS "Adding linker flags for GLVND.")
endif()

if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
  set(warn_disable_flags
    "-Weverything"

    # Disabled warnings that are overly verbose right now or just do not make sense.
    "-Wno-c++98-compat"
    "-Wno-c++98-compat-pedantic"
    "-Wno-conversion"
    "-Wno-exit-time-destructors"
    "-Wno-global-constructors"
    "-Wno-padded"
    "-Wno-sign-conversion"
    "-Wno-missing-noreturn"

    # It is impossible to write code that both GCC and Clang will like,
    # so we have to switch off the warning for one of them.
    # http://clang-developers.42468.n3.nabble.com/Question-on-Wswitch-enum-td4025927.html
    "-Wno-switch-enum"

    # TODO(sirver: weak-vtables should be enabled, but leads to lot of errors right now.
    "-Wno-weak-vtables"
    "-Wno-unreachable-code"
    "-Wno-documentation"
    "-Qunused-arguments"
    "-Wint-to-void-pointer-cast"
  )
  foreach(flag IN LISTS warn_disable_flags)
    wl_add_flag(WL_COMPILE_DIAGNOSTICS ${flag})
  endforeach()

  if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 3.8)
    wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Winconsistent-missing-override")
  endif()
elseif(MSVC)
  # https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/
  # Disabled warnings that are overly verbose right now or just do not make sense.
  wl_add_flag(WL_COMPILE_DIAGNOSTICS "/wd4244")
  wl_add_flag(WL_COMPILE_DIAGNOSTICS "/wd4267")
  wl_add_flag(WL_COMPILE_DIAGNOSTICS "/wd4018")
  # Use correct code page
  wl_add_flag(WL_GENERIC_CXX_FLAGS "/utf-8")
else()
  # Assuming GCC 4.8 or higher.
  if(WIN32)
    # This is needed for getenv().
    wl_add_flag(WL_GENERIC_CXX_FLAGS "-std=gnu++11")
    if (OPTION_BUILD_WINSTATIC)
      set(CMAKE_CXX_STANDARD_LIBRARIES "-static-libgcc -static-libstdc++ ${CMAKE_CXX_STANDARD_LIBRARIES}")
      set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-Bstatic")
    endif()
  else()
    # SDL and MinGW both declare 'unsigned int __builtin_ia32_crc32qi(unsigned int, unsigned char)', resulting in lots of warnings. So, we can't have this flag in Windows.
    wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Wredundant-decls")
  endif()

  set(warn_flags
    "-Wall"
    "-Wpedantic"
    "-Wdeprecated-declarations"
    "-Wextra"
    "-Wformat"
    "-Wformat-nonliteral"
    "-Wformat-security"
    "-Wformat-y2k"
    "-Winit-self"
    "-Winvalid-pch"
    "-Wlogical-op"
    "-Wmissing-include-dirs"
    "-Wno-undef"
    "-Wold-style-cast"
    "-Woverlength-strings"
    "-Wpacked"
    "-Wpointer-arith"
    "-Wsign-promo"
    "-Wsync-nand"
    "-Wtrampolines"
    "-Wundef"
    "-Wunused"
    "-Wunused-macros"
    "-fno-elide-constructors" # Detect invalid constexpr initialization
  )
  foreach(flag IN LISTS warn_flags)
    wl_add_flag(WL_COMPILE_DIAGNOSTICS ${flag})
  endforeach()
endif()

if(NOT MSVC)
  if(CMAKE_BUILD_TYPE STREQUAL "Release")
    message(STATUS "Compiler warnings will be ignored.")
  elseif(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") AND 
         (NOT (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 12.0)) AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 12.2))
    # Skip this on g++12.0 and 12.1 because of false-positives from system headers.
    message(WARNING "This compiler is known to cause false-positive warnings.")
  else()
    # Turn some warnings into errors.
    message(STATUS "Warnings will be treated as errors.")
    wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Werror")
    if(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 10.0))
      # Silence some false positives on older g++
      message(STATUS "Disabling known false-positive warnings for this compiler.")
      wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Wno-error=unused-variable")
      wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Wno-error=unused-but-set-parameter")
    endif()
    if (APPLE)  # Our Mac CI needs these
      message(STATUS "Disabling known false-positive warnings for this environment.")
      wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Wno-error=poison-system-directories")
      wl_add_flag(WL_COMPILE_DIAGNOSTICS "-Wno-error=disabled-macro-expansion")
    endif()
  endif()

  wl_add_flag(WL_GENERIC_CXX_FLAGS "-std=c++11")
endif()

# Cross-compile-unit optimization slows linking significantly.
# Therefore, impatient user may want to prevent that.
if(USE_FLTO_IF_AVAILABLE STREQUAL "yes")
# Cross-compile-unit optimization not supported by gcc with debug on!
# Therefore, this may only be done with Release builds.
if(CMAKE_BUILD_TYPE STREQUAL "Release")
  # Only tested on Linux. Might work also on other platforms.
  # If tested and found good, remove this check
  if (CMAKE_SYSTEM MATCHES "Linux")
    # Usage of -flto tested only with gcc 8.3 and 9.3 (2020-04); when in doubt, leaving it out..
    if(("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU") AND (CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 8.0))
      #
      # The execution jumps between compile units rather often. -flot allows optimization across
      # comple units. Binary size reduced by >15% on tested environments. This does not directly
      # translate to execution speed, but might still be noticeable.
      #
      # This is not related to -O2 or -O3 discussion, and not enable by either.
      #
      # If using lto, it needs to happen both during compile and link, else no benefits.
      wl_add_flag(WL_GENERIC_CXX_FLAGS "-flto")
      SET(CMAKE_EXE_LINKER_FLAGS  "${CMAKE_EXE_LINKER_FLAGS} -flto")
      message(STATUS "Enabling link-time optimizations")
    endif()
  endif(CMAKE_SYSTEM MATCHES "Linux")
endif(CMAKE_BUILD_TYPE STREQUAL "Release")
endif(USE_FLTO_IF_AVAILABLE STREQUAL  "yes")

IF (WIN32)
  add_definitions(-D_WIN32_WINNT=0x0601)
  if(MSVC)
    add_definitions(-DWIN32_LEAN_AND_MEAN -D__STDC_FORMAT_MACROS -DNOMINMAX)
    # Needed for minizip
    add_definitions(-Dor=|| -Dand=&& -Dnot=!)
    if (OPTION_BUILD_WINSTATIC)
      set(BROTLI brotlidec-static brotlicommon-static brotlienc-static)
      set(SDL_EXTRA_LIBS charset)
      if(CMAKE_BUILD_TYPE STREQUAL "Debug")
        string(REPLACE "/MDd" "" CMAKE_CXX_FLAGS_DEBUG ${CMAKE_CXX_FLAGS_DEBUG})
        wl_add_flag(TARGET_COMPILE_FLAGS "/MTd /EHsc")
      else()
        string(REPLACE "/MD" "" CMAKE_CXX_FLAGS_RELEASE ${CMAKE_CXX_FLAGS_RELEASE})
        wl_add_flag(TARGET_COMPILE_FLAGS "/MT /EHsc")
      endif()
    endif()
  else()
    # Fix static library dependencies
    set(ZSTD zstd)
    set(BROTLI brotlidec brotlicommon brotlienc)
    set(SDL_MIXER_EXTRA_LIBS ssp)
    set(SDL_EXTRA_LIBS mingw32 dxerr8)
    set(SDL_IMG_EXTRA_LIBS jbig deflate Lerc jxl hwy)
    add_definitions(-DMINGW_HAS_SECURE_API -DWIN32_LEAN_AND_MEAN -D__STDC_FORMAT_MACROS -D__USE_MINGW_ANSI_STDIO)
    if (CMAKE_SIZEOF_VOID_P EQUAL 4)
      set (CMAKE_EXE_LINKER_FLAGS "-Wl,--large-address-aware" CACHE STRING "Set by widelands CMakeLists.txt" FORCE)
      message (STATUS "Enabled large address awareness on mingw32")
    else (CMAKE_SIZEOF_VOID_P EQUAL 4)
      message (STATUS "Detected mingw32-w64")
    endif (CMAKE_SIZEOF_VOID_P EQUAL 4)
  endif()
endif (WIN32)

# on BSD this must be explicitly linked
if (CMAKE_SYSTEM_NAME MATCHES "FreeBSD" OR CMAKE_SYSTEM_NAME MATCHES "OpenBSD")
  # Not needed on Debian GNU/kFreeBSD..
  if (NOT CMAKE_SYSTEM_NAME MATCHES "kFreeBSD")
    find_library(EXECINFO_LIBRARY NAMES execinfo)
  endif (NOT CMAKE_SYSTEM_NAME MATCHES "kFreeBSD")

  # OpenBSD needs the X11 include directory in order to find GL/glu.h
  if (CMAKE_SYSTEM_NAME MATCHES "OpenBSD")
    find_package(X11 REQUIRED)
    include_directories(${X11_INCLUDE_DIR})
  endif ()
endif (CMAKE_SYSTEM_NAME MATCHES "FreeBSD" OR CMAKE_SYSTEM_NAME MATCHES "OpenBSD")

if (NOT DEFINED WL_VERSION)
  include (${CMAKE_SOURCE_DIR}/cmake/BzrRevision.cmake)
else (NOT DEFINED WL_VERSION)
  add_custom_target (
    InputRevision ALL
    COMMAND ${CMAKE_COMMAND} -DWL_INSTALL_BASEDIR=${WL_INSTALL_BASEDIR} -DWL_VERSION=${WL_VERSION} -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE} -DSOURCE_DIR=${CMAKE_CURRENT_SOURCE_DIR} -DBINARY_DIR=${CMAKE_CURRENT_BINARY_DIR} -P ${CMAKE_CURRENT_SOURCE_DIR}/cmake/InputRevision.cmake
  )
endif (NOT DEFINED WL_VERSION)

# Enable testing.
if (OPTION_BUILD_TESTS)
  include(CTest)
  enable_testing()

  # Run a test after a normal compile. This magic is needed as 'make test' will
  # not rebuild tests:
  # https://stackoverflow.com/questions/733475/cmake-ctest-make-test-doesnt-build-tests
  add_custom_target(_run_all_tests ALL
    COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure
    WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
    DEPENDS wl_tests
  )
endif (OPTION_BUILD_TESTS)

install (
  FILES ${CMAKE_CURRENT_BINARY_DIR}/VERSION
  DESTINATION ${WL_INSTALL_BASEDIR}
  CONFIGURATIONS Debug;Release;None
  COMPONENT CoreVersionFile
)

# Installation.
add_subdirectory(doc)
if(OPTION_BUILD_TRANSLATIONS)
  add_subdirectory(po)
endif(OPTION_BUILD_TRANSLATIONS)
add_subdirectory(src)

# install files to the correct locations here
install(
  FILES
    data/datadirversion
  DESTINATION ${WL_INSTALL_DATADIR}
  CONFIGURATIONS Debug;Release;None
  COMPONENT VersionFile
)

install(
  DIRECTORY
    data/ai
    data/campaigns
    data/i18n
    data/images
    data/scripting
    data/shaders
    data/templates
    data/tribes
    data/txts
    data/world
  DESTINATION ${WL_INSTALL_DATADIR}
  CONFIGURATIONS Debug;Release;None
  COMPONENT CoreDataFiles
)

install(
  DIRECTORY
    data/maps
  DESTINATION ${WL_INSTALL_DATADIR}
  CONFIGURATIONS Debug;Release;None
  COMPONENT MapFiles
)

install(
  DIRECTORY
    data/music
    data/sound
  DESTINATION ${WL_INSTALL_DATADIR}
  CONFIGURATIONS Debug;Release;None
  COMPONENT MusicFiles
)

install(
  FILES
    COPYING
    CREDITS
    ChangeLog
  DESTINATION ${WL_INSTALL_BASEDIR}
  CONFIGURATIONS Debug;Release;None
  COMPONENT CoreLicenseFiles
)

install(
  DIRECTORY
    doc
  DESTINATION ${WL_INSTALL_BASEDIR}
  CONFIGURATIONS Debug
  COMPONENT DocFiles
  PATTERN "CMakeLists.txt" EXCLUDE
)

if(OPTION_BUILD_TRANSLATIONS)
  set_directory_properties(PROPERTIES ADDITIONAL_MAKE_CLEAN_FILES ${WL_INSTALL_DATADIR}/locale)
  install(
    DIRECTORY
      ${CMAKE_CURRENT_BINARY_DIR}/locale/
    DESTINATION ${WL_INSTALL_DATADIR}/locale
    CONFIGURATIONS Debug;Release;None
    COMPONENT CoreLanguageFiles
  )
endif(OPTION_BUILD_TRANSLATIONS)

if (UNIX AND NOT APPLE)
  add_subdirectory(xdg)
endif (UNIX AND NOT APPLE)

# uninstall target
# see https://gitlab.kitware.com/cmake/community/-/wikis/FAQ#can-i-do-make-uninstall-with-cmake
if(NOT TARGET uninstall)
  configure_file(
    "${CMAKE_CURRENT_SOURCE_DIR}/cmake/cmake_uninstall.cmake.in"
    "${CMAKE_CURRENT_BINARY_DIR}/cmake/cmake_uninstall.cmake"
    IMMEDIATE @ONLY)

  add_custom_target(uninstall
    COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_BINARY_DIR}/cmake/cmake_uninstall.cmake)
endif()